Already quite highly developed user interface concepts are known at present from electronic portable devices, such as mobile stations, PDA (Personal Digital Assistant) devices, and digital cameras. The user interface visualized on the display of the device is used to control the functions of the device and through that can also be input or examine information presented in applications. The simplest implementation of a user interface according to the prior art is, for example, as hierarchal menu solutions.
Various graphical user interfaces (GUI, Graphical User Interface), which are represented, for example, by various icon-type solutions, are already known from some more highly developed electronic devices. Generally, the display component of the device, which nowadays can be implemented in colour, is used to show the user interface to the user.
In some already existing devices, or at least in devices that it is intended to bring onto the market in the future, various three-dimensional displays and/or 3D user-interface/application environments will become common. Such displays can be applied, for example, in game applications.
The prior art for controlling the user interfaces and applications of the devices, and for processing information is represented by various moveable indicator element type solutions. Some examples of these are pointer cursors and menu selectors. In the most basic of these solutions, the currently active selection alternative can be shown in a way that distinguishes it from the other alternatives. In graphical user interfaces, the position and directions of movement of the pointer cursor, which can be shown on the display component using, for example, some graphical element, can be nearly arbitrary. Thus, for example, when selecting a desired selection alternative, the control means of the user interface are used to move the pointer cursor on top of the desired selection item, and the selection is confirmed.
In this case, the control means can be understood as being various data entry means in general, so that besides moving the pointer cursor, they can be used, for example, to navigate the menus, to control the behaviour of characters in game applications, to enter information such as such text in the device, to make selections, to activate applications, and in general to control the operation of the device.
Numerous different control-means solutions for moving the pointer cursor are known, by means of which data can also be entered in the device. Some examples of these are a keypad, special keys located in the keypad component, such as, for example, navigation keys, and joystick controllers. Their operating principle is generally based on a vector, the direction of which is defined by the user using the control means.
In addition to the above, various touchscreens can also be mentioned, touching which allows the pointer cursor to be moved in the user interface. Some devices are also known, in which there is no actual data-entry mechanism at all. As one example a reference can be made to a voice control implemented using a microphone.
A special user panel, using which a pointer cursor visualized in the user interface can be controlled, and which can be arranged on rear side, i.e. the side opposite to the display component, of the portable device, is known from WO patent publication 02/093880 A2. This too is a case of a touch-sensitive base, on the surface of which the user can move their finger, while holding the device in the same hand.
Although such a device frees the other hand for other tasks, it is nevertheless relatively impractical, for example, from the user's point of view. The touch-sensitive panel arranged on the rear side of the device specially for controlling the pointer cursor increases the manufacturing costs of the device and is also liable to be knocked. In addition, when holding the device in one hand, while using a finger of the same hand to control the pointer cursor, the operating position of the hand and fingers is in no way ergonomic, instead the finger is subject to considerable stress when moving over the panel. This drawback is particularly aggravated when the solution is applied in small devices.
As one data-entry/control method, reference can also be made to the use of acceleration sensors for determining the movements affecting a device and, as a result, for moving the element. In this case, the sensor can determine the movement, or change in position or location relative to a fixed point, affecting the device, from which a direction vector can be formed, according to which the element is then controlled in the user interface. In such a use situation, the user can, for example, if desired navigate to the next theme on the right, by turning the device slightly to the right and then turning it back towards themselves.
However, the data-entry solutions referred to above, which mainly relate in one way or another to the use of fingers, are difficult to control, for example, when wearing gloves. Due to their small size, the keys are outside of the resolution of the gloves, and keying errors can't always be unavoidable. When such a situation arises, it is very unpleasant for the user, as it shows a obvious defect in the smooth usability of the devices.
Yet another solution known from the prior art for controlling the functions of a device is the application of image information formed using camera means. When changing the direction of aim of the camera means, a directional vector, on the basis of which the functions of the device can be controlled, can be determined from sequentially captured shots. Such solutions are disclosed in, among others, Swedish patent publication 9902562-9 (Telefonaktiebolaget L M Ericsson) and British patent application GB 2 387 755 (NEC Corporation). Some other solutions are disclosed in US patent publication 2004/0012566 A1, U.S. Pat. No. 6,288,704 B1, WO publication 2004/066615, and US patent publication 2004/0085455 A1.
The only ‘finger-free’ user interface's control and data entry method of those referred to above are the voice control of the device and the application of acceleration sensors and information formed using camera means. However, due to the diversity of the functions of the devices, the complexity of the user interfaces, and even their three-dimensionality, such forms of control are not, at least yet, at all easy to implement in terms of usability. The forms of implementation referred to above cannot be used to enter information into the device smoothly, or at all, to activate the functions of the device, or to control more complex applications, without the use of fingers. In addition, using acceleration/orientation sensors may involve not only making the devices more complicated, but also problems on the hardware level. The application of camera means may also reduce the precision of the cursor indication.